1. Technical Field
This invention relates to active noise control, and more specifically to active noise control used with an audio system.
2. Related Art
Active noise control may be used to generate sound waves that destructively interfere with a targeted sound. The destructively interfering sound waves may be produced through a loudspeaker to combine with the targeted sound. Active noise control may be desired in a situation in which audio sound waves, such as music, may be desired as well. An audio/visual system may include various loudspeakers to generate audio. These loudspeakers may be simultaneously used to produce destructively interfering sound waves.
An active noise control system generally includes a microphone to detect sound proximate to an area targeted for destructive interference. The detected sound provides an error signal in which to adjust the destructively interfering sound waves. However, if audio is also generated through a common loudspeaker, the microphone may detect the audio sound waves, which may be included in the error signal. Thus, the active noise control may track sounds not desired to be interfered with, such as the audio. This may lead to inaccurately generated destructive interference. Furthermore, the active noise control system may generate sound waves to destructively interfere with the audio. Therefore, a need exists to remove an audio component from an error signal in an active noise control system.